Augers and belt conveyors are commonly used to move dry matter such as grain, fertilizer, and feed material between storage and transport containers. Recently there has been an increase in the use of large augers and hopper bottom highway trailers by grain growers. Hopper bottom trailers being designed for unloading at large handling facilities introduce some handling problems at the growers level because the storage containers may not be located in one location and it may be necessary to unload hopper bottom trailers at many different locations. The initial solution to doing this was using a swinging transfer auger to take the material from the bottom of the trailer to the bottom of the main auger. The main auger then transfers the material into the storage bin. The main difficulty with this solution is that the swinging auger must be moved under the trailer while the trailer is driving alongside the auger into position. This requires 2 people, one to drive, one to swing the transfer auger. This is prone to accidents if there is miscommunication between the 2 people or if there is not enough clearance or the ground is too rough, the hopper on the transfer auger often gets run over. As the size of the augers continues to increase it compounds the problem as the transfer auger becomes too heavy for one person to move. There have been inventions to drive the wheels on the swing auger to make the task of swinging the auger easier. There have also been inventions for remote control of the drive on the wheels of the transfer auger to make it possible for one person to swing the auger under the trailer while driving. The solution is still not ideal because it is very difficult to see and effectively control something that far behind the driver. Another solution is to use a belt conveyor that can be extended under the trailer after the trailer is in place. The belt conveyor is retracted before the trailer is moved. It can swing as well to pick up more than one hopper without moving the trailer if required. Operationally this is a very good solution because large capacity is possible; the task can easily be done by one person with mechanical assists, and the transfer conveyor can be extended after the trailer is in place, reducing the risk of injury and damage. However, mechanically it is expensive to build a belt conveyor compared to a screw conveyor (auger) and the cost is multiplied by adding the mechanisms required to make an extending, retracting, (telescoping) belt conveyor.
Canadian Patent 2398015 is an apparatus to accomplish the same function, but it does so with a belt conveyor, and is telescoping in that it is functional at any point in its travel.
Canadian Patent 1137915 is an apparatus that could be used to accomplish the same function. It is an extensible or telescoping auger which is also functional at any point in its travel. It references other extensible auger patents as well.
U.S. Pat. No. 7,381,131 is an apparatus that is an extendable auger, however its outlet moves and inlet is fixed, so it is somewhat telescoping in that it can function over a significant portion of its travel, however it is similar to our invention in that if it were to travel too far it would not function, ie the material would be deposited in the wrong place. It also uses telescoping casings.